2017 年 36 巻 1 号 p. 59-63
Tibial shaft spiral fractures are often associated with proximal fibula fractures. Although not well known, posterior malleolar fractures are sometimes involved in tibial shaft spiral fractures.
We report three cases of occult posterior malleolar fractures associated with tibial shaft fractures.
In all three cases posterior malleolar fractures were recognized initially on plain radiographs. In one case a posterior malleolar fracture was retrospectively noted on computed tomography (CT) scans after intramedullary nailing of the tibial shaft fracture. In the other two cases posterior malleolar fractures were detected on CT scans and were stabilized with a cannulated screw before nailing of the tibial shaft fractures. Missed and untreated posterior malleolar fractures may influence the progress of postoperative rehabilitation and lead to ankle osteoarthritis.
A high index of suspicion is required in the treatment of tibial spiral shaft fractures. We recommend CT evaluation in search for posterior malleolar fractures in patients with tibial spiral shaft fractures.